The present invention generally relates to locks and, more particularly, to locks used to prevent the theft of a vehicle spare tire.
The spare wheel and tire for a vehicle normally exhibits a high replacement cost. This is particularly true for vehicles such as pick-up trucks and sport utility vehicles, which typically must carry a full-size spare wheel and tire. Unfortunately, theft of such valuable spare tires is a pervasive problem, especially for vehicles such as pick-up trucks and SUVs, which often mount the spare wheel and tire below the vehicle frame, suspended by a winch-driven cable. For example, it is not uncommon for franchised new truck dealers to have many spare tires stolen from the trucks while they are stored or displayed on the dealer""s lot. Private owners of these vehicles also experience similar problems.
Because of these theft concerns, it is desirable to provide a means for locking the spare tire (and the corresponding wheel) to the vehicle in order to prevent theft. It is particularly desirable to provide a device which can be added to the already manufactured vehicle without modification to the vehicle.
Various devices have been developed in the past to lock an under-frame mounted spare tire to the vehicle. For example, my previous patent, U.S. Pat. No. 4,794,771, comprises a bar which is suspended from the metal spare tire winch tube and extends through the spare wheel. A lock is fastened to the end of the bar in order to securely lock the wheel to the vehicle. The which tube in this previous design is a solid metal tube that is rotated to operate the winch, and therefore is structurally solid enough to support the spare tire lock bar. This design has proven to be an exemplary protection device for many vehicle designs, however, some manufacturers of vehicles such as pick-up trucks are now employing a plastic winch tube on the vehicles which limits the usefulness of my prior art design, because this plastic winch tube only serves to guide the winch rotation tool to the winch and is not structurally suited to support the spare tire lock bar.
With reference to FIG. 1, there is shown a prior art spare tire winch mechanism, such as those currently found on many pick-up trucks, as viewed from the underside of the vehicle. The prior art winch assembly is generally indicated at 10. The winch assembly 10 includes a winch mechanism 12 mounted to the underside of the vehicle frame 14 by means of a bolt-on bracket 16. A cable 18 extends from the bottom surface of the winch 12 and is attached to the spare wheel/tire (not shown) in order to raise and lower same from underneath the vehicle. Extension and retraction of the cable 18 is accomplished by rotation of the square post 20.
In order to provide convenient access to the square post 20 from the rear of the vehicle, a plastic winch tube 22 covers the square post 20 and extends to the rear of the vehicle through an opening in the vehicle bumper (not shown). This allows an elongated tool to be inserted into the winch tube 22 from the rear of the vehicle, such that the tool engages the square post 20, whereupon the tool may be rotated in order to raise and lower the winch cable 18 (and hence the spare wheel/tire). In order to prevent unauthorized access to the winch 12, the vehicle manufacturer provides a lock cylinder 24 which lockingly engages the open end of the winch tube 22 at the rear bumper, thereby preventing access to the square post 20 until the lock cylinder 24 is unlocked and removed from the winch tube 22.
This prior art security means provided by the manufacturer has proven to be relatively ineffective because it can be defeated by a thief in many different ways. For example, six different ways to easily defeat the prior art factory-installed winch mechanism lock are illustrated in FIGS. 2A-F. FIG. 2A illustrates the rear bumper of the vehicle, where access is provided to the lock cylinder 24 at the end of the winch tube 22. A screwdriver 26 or small pry bar may be placed under the flange edge of the plastic lock housing which forms the proximal end of the winch tube 22. This flange edge will break away in several pieces when pried upon, allowing the lock housing to be pushed through the vehicle bumper. Reaching up behind the bumper will then allow the broken lock housing to be removed from the end of the winch tube 22 with the lock cylinder still locked inside. Access may then be had to the square post 20, which operates the winch 12.
As shown in FIG. 2B, there is a small raised cavity 28 on the lower side of the plastic lock housing just behind the rear bumper. Using an ice pick held with the pointed end angled slightly to the rear of the vehicle, a small hole may be made in the bottom of the cavity 28. Pushing the end of the ice pick in through the hole will depress the spring-loaded lock bolt, releasing the lock cylinder from the end of the lock housing. Access may then be had to the square shaft 20, which operates the winch 12.
Referring to FIG. 2C, a pair of pliers 30 may be clamped around the plastic winch tube 22 from the backside of the rear vehicle bumper, and rotated. Such an attempt to turn the lock housing in its square mounting hole will crack and break the edge of the steel retainer ring, which holds it in place. Pulling down on what remains of the broken lock housing will release the lock cylinder from the part of the lock housing which is still installed in the rear vehicle bumper. Access may then be had to the square shaft 20 which operates the winch 12.
Referring to FIG. 2D, the plastic winch tube 22 may be reached above the spare tire from the right side of the vehicle. Grasping the winch tube 22 and pulling downward sharply will release the winch tube 22 from its mounting location over the square shaft 20. The square shaft 20 can now be accessed through the large rectangular hole in the center of the rear bumper.
Referring to FIG. 2E, only one mounting bolt 32 attaches the winch 12 to the vehicle frame. A new spare wheel design with large center hub openings allows easy access to the mounting bolt 32. Removing this bolt 32 releases the winch mechanism 12 from the frame 14, with the spare tire still attached.
Referring to FIG. 2F, a quick and easy way to defeat most spare tire locks is to simply cut the winch cable 18 above the spare wheel. The new wheel design with larger center hub openings now allows unrestricted access to cut the winch cable 18.
It can be seen from the above examples that there are numerous ways to easily defeat the factory supplied spare tire lock system. There is therefore a need for an alternative spare wheel/tire lock design which cannot be defeated by any of these methods. The present invention is directed toward meeting this need.
The present invention relates to a spare tire lock which installs through an opening in the vehicle frame in order to suspend a locking bar down through an opening (preferably the lug nut hole) in the spare wheel. A locking device may then be slid over the distal end of the locking bar in order to lock the spare wheel securely in place. The locking device is designed to accept a lock cylinder from the manufacturer""s easily-defeated spare tire lock, so that the locking device of the present invention may be keyed with the remaining locks of the vehicle. The locking mechanism of the present invention also incorporates a spring-loaded resilient boot which engages the vehicle spare wheel lug nut hole and eliminates excessive end play, thereby preventing annoying rattling between the spare tire lock of the present invention and the spare tire.
In one form of the invention, a spare tire lock for securing a spare wheel and tire suspended under a vehicle having a frame is disclosed, said spare tire lock comprising a lock bar having a proximal end and a distal end, the lock bar proximal end being coupled to said vehicle frame, wherein said lock bar extends through an opening in said spare wheel, such that the proximal and distal ends of said lock bar are on opposite sides of said spare wheel; and a locking mechanism releasably coupled to the distal end of said lock bar.
In another form of the invention, a method of locking spare wheel and tire suspended under a vehicle having a frame, a pre-existing winch for raising and lowering the spare wheel, and a pre-existing lock for locking the pre-existing winch, is disclosed comprising the steps of: a) providing a lock bar having a proximal end and a distal end; b) coupling the lock bar proximal end to the frame; c) removing a lock cylinder from the pre-existing lock; d) extending the distal end of the lock bar through an opening in the spare wheel, such that the proximal and distal ends of the lock bar are on opposite sides of the spare wheel; e) providing a locking mechanism housing having a cavity therein for accepting a locking device; f) inserting the lock cylinder from the pre-existing lock into the cavity in the locking mechanism housing; and g) lockingly coupling the locking mechanism to the distal end of the lock bar.